At 01:52 PM 11/22/00 -0800, Sergey Melnik wrote:
>Pierre-Antoine CHAMPIN wrote:
> > ...
> > First, Statements and Reified statements are not the same thing.
>
>Although this is consistent with the spec, I believe there are
>significant advantages both for understanding and manipulating reified
>statements if these two notions are merged into one.
>
>Can you (or anyone) list some use cases where it is beneficial to make
>this distinction? I can think of several cases, in which distinguishing
>statements vs. reified statements makes things a lot more complicated.
>Just consider a database query that retrieves all assertions made about
>a statement (by anyone).
I think it is necessary to distinguish between 'statings' and 'quotings' of
statements. Reification is a way to do that within the RDF model as
currently defined. Are there others?
[...]
>The "fix" or interpretation I advocate is the following:
>
>- STATEMENTS ARE RESOURCES (that implies that every statement is unique
>and equivalent to reified statement)
>- toss "quad" reification mechanism altogether
As I follow this debate, I become more convinced that the idea of a
reification as a "model" of a statement is most helpful. It allows us to
create such a model, with associated resource ID, so we can make statements
like "A statement of the form [p s o] was asserted and signed by Alice",
and also "A statement of the form [p s o] was asserted and signed by
Bob". Here, we actually _need_ two separate resources to express this
without also saying "A statement of the form [p s o] was asserted by Alice
and signed by Bob".
Thus, I suggest, we actually need to be able to have multiple resources
representing a given statement. The RDF model achieves this through
reification. The XML syntax and any implementation may provide a shorthand
for the reification quad.
#g
------------
Graham Klyne
(GK@ACM.ORG)